// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/audio/simple_sources.h"

#include <stddef.h>
#include <stdint.h>

#include <limits>
#include <memory>

#include "base/files/file_util.h"
#include "base/logging.h"
#include "base/time/time.h"
#include "media/audio/sounds/test_data.h"
#include "media/base/audio_bus.h"
#include "media/base/audio_parameters.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace media {

// Validate that the SineWaveAudioSource writes the expected values.
TEST(SimpleSources, SineWaveAudioSource)
{
    static const uint32_t samples = 1024;
    static const uint32_t bytes_per_sample = 2;
    static const int freq = 200;

    AudioParameters params(
        AudioParameters::AUDIO_PCM_LINEAR, CHANNEL_LAYOUT_MONO,
        AudioParameters::kTelephoneSampleRate, bytes_per_sample * 8, samples);

    SineWaveAudioSource source(1, freq, params.sample_rate());
    std::unique_ptr<AudioBus> audio_bus = AudioBus::Create(params);
    source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
        audio_bus.get());
    EXPECT_EQ(1, source.callbacks());
    EXPECT_EQ(0, source.errors());

    uint32_t half_period = AudioParameters::kTelephoneSampleRate / (freq * 2);

    // Spot test positive incursion of sine wave.
    EXPECT_NEAR(0, audio_bus->channel(0)[0],
        std::numeric_limits<float>::epsilon());
    EXPECT_FLOAT_EQ(0.15643446f, audio_bus->channel(0)[1]);
    EXPECT_LT(audio_bus->channel(0)[1], audio_bus->channel(0)[2]);
    EXPECT_LT(audio_bus->channel(0)[2], audio_bus->channel(0)[3]);
    // Spot test negative incursion of sine wave.
    EXPECT_NEAR(0, audio_bus->channel(0)[half_period],
        std::numeric_limits<float>::epsilon());
    EXPECT_FLOAT_EQ(-0.15643446f, audio_bus->channel(0)[half_period + 1]);
    EXPECT_GT(audio_bus->channel(0)[half_period + 1],
        audio_bus->channel(0)[half_period + 2]);
    EXPECT_GT(audio_bus->channel(0)[half_period + 2],
        audio_bus->channel(0)[half_period + 3]);
}

TEST(SimpleSources, SineWaveAudioCapped)
{
    SineWaveAudioSource source(1, 200, AudioParameters::kTelephoneSampleRate);

    static const int kSampleCap = 100;
    source.CapSamples(kSampleCap);

    std::unique_ptr<AudioBus> audio_bus = AudioBus::Create(1, 2 * kSampleCap);
    EXPECT_EQ(source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
                  audio_bus.get()),
        kSampleCap);
    EXPECT_EQ(1, source.callbacks());
    EXPECT_EQ(source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
                  audio_bus.get()),
        0);
    EXPECT_EQ(2, source.callbacks());
    source.Reset();
    EXPECT_EQ(source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
                  audio_bus.get()),
        kSampleCap);
    EXPECT_EQ(3, source.callbacks());
    EXPECT_EQ(0, source.errors());
}

TEST(SimpleSources, OnError)
{
    SineWaveAudioSource source(1, 200, AudioParameters::kTelephoneSampleRate);
    source.OnError(NULL);
    EXPECT_EQ(1, source.errors());
    source.OnError(NULL);
    EXPECT_EQ(2, source.errors());
}

void VerifyContainsTestFile(const AudioBus* audio_bus)
{
    // Convert the test data (little-endian) into floats and compare. We need to
    // index past the first bytes in the data, which contain the wav header.
    const int kFirstSampleIndex = 12 + 8 + 16 + 8;
    int16_t data[2];
    data[0] = kTestAudioData[kFirstSampleIndex];
    data[0] |= (kTestAudioData[kFirstSampleIndex + 1] << 8);
    data[1] = kTestAudioData[kFirstSampleIndex + 2];
    data[1] |= (kTestAudioData[kFirstSampleIndex + 3] << 8);

    // The first frame should hold the WAV data.
    EXPECT_FLOAT_EQ(static_cast<float>(data[0]) / ((1 << 15) - 1),
        audio_bus->channel(0)[0]);
    EXPECT_FLOAT_EQ(static_cast<float>(data[1]) / ((1 << 15) - 1),
        audio_bus->channel(1)[0]);

    // All other frames should be zero-padded. This applies even when looping, as
    // the looping will restart on the next call to OnMoreData.
    for (int channel = 0; channel < audio_bus->channels(); ++channel) {
        for (int frame = 1; frame < audio_bus->frames(); ++frame) {
            EXPECT_FLOAT_EQ(0.0, audio_bus->channel(channel)[frame]);
        }
    }
}

TEST(SimpleSources, FileSourceTestDataWithoutLooping)
{
    const int kNumFrames = 10;

    // Create a temporary file filled with WAV data.
    base::FilePath temp_path;
    ASSERT_TRUE(base::CreateTemporaryFile(&temp_path));
    base::File temp(temp_path,
        base::File::FLAG_WRITE | base::File::FLAG_OPEN_ALWAYS);
    temp.WriteAtCurrentPos(kTestAudioData, kTestAudioDataSize);
    ASSERT_EQ(kTestAudioDataSize, static_cast<size_t>(temp.GetLength()));
    temp.Close();

    // Create AudioParameters which match those in the WAV data.
    AudioParameters params(AudioParameters::AUDIO_PCM_LINEAR,
        CHANNEL_LAYOUT_STEREO, 48000, 16, kNumFrames);
    std::unique_ptr<AudioBus> audio_bus = AudioBus::Create(2, kNumFrames);
    audio_bus->Zero();

    // Create a FileSource that reads this file.
    bool loop = false;
    FileSource source(params, temp_path, loop);
    EXPECT_EQ(kNumFrames,
        source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
            audio_bus.get()));

    VerifyContainsTestFile(audio_bus.get());

    // We should not play any more audio after the file reaches its end.
    audio_bus->Zero();
    source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
        audio_bus.get());
    for (int channel = 0; channel < audio_bus->channels(); ++channel) {
        for (int frame = 0; frame < audio_bus->frames(); ++frame) {
            EXPECT_FLOAT_EQ(0.0, audio_bus->channel(channel)[frame]);
        }
    }
}

TEST(SimpleSources, FileSourceTestDataWithLooping)
{
    const int kNumFrames = 10;

    // Create a temporary file filled with WAV data.
    base::FilePath temp_path;
    ASSERT_TRUE(base::CreateTemporaryFile(&temp_path));
    base::File temp(temp_path,
        base::File::FLAG_WRITE | base::File::FLAG_OPEN_ALWAYS);
    temp.WriteAtCurrentPos(kTestAudioData, kTestAudioDataSize);
    ASSERT_EQ(kTestAudioDataSize, static_cast<size_t>(temp.GetLength()));
    temp.Close();

    // Create AudioParameters which match those in the WAV data.
    AudioParameters params(AudioParameters::AUDIO_PCM_LINEAR,
        CHANNEL_LAYOUT_STEREO, 48000, 16, kNumFrames);
    std::unique_ptr<AudioBus> audio_bus = AudioBus::Create(2, kNumFrames);
    audio_bus->Zero();

    bool loop = true;
    FileSource source(params, temp_path, loop);

    // Verify that we keep reading in the file when looping.
    source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
        audio_bus.get());
    audio_bus->Zero();
    source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0,
        audio_bus.get());

    VerifyContainsTestFile(audio_bus.get());
}

TEST(SimpleSources, BadFilePathFails)
{
    AudioParameters params(AudioParameters::AUDIO_PCM_LINEAR,
        CHANNEL_LAYOUT_STEREO, 48000, 16, 10);
    std::unique_ptr<AudioBus> audio_bus = AudioBus::Create(2, 10);
    audio_bus->Zero();

    // Create a FileSource that reads this file.
    base::FilePath path;
    path = path.Append(FILE_PATH_LITERAL("does"))
               .Append(FILE_PATH_LITERAL("not"))
               .Append(FILE_PATH_LITERAL("exist"));
    bool loop = false;
    FileSource source(params, path, loop);
    EXPECT_EQ(0, source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0, audio_bus.get()));

    // Confirm all frames are zero-padded.
    for (int channel = 0; channel < audio_bus->channels(); ++channel) {
        for (int frame = 0; frame < audio_bus->frames(); ++frame) {
            EXPECT_FLOAT_EQ(0.0, audio_bus->channel(channel)[frame]);
        }
    }
}

TEST(SimpleSources, FileSourceCorruptTestDataFails)
{
    const int kNumFrames = 10;

    // Create a temporary file filled with WAV data.
    base::FilePath temp_path;
    ASSERT_TRUE(base::CreateTemporaryFile(&temp_path));
    base::File temp(temp_path,
        base::File::FLAG_WRITE | base::File::FLAG_OPEN_ALWAYS);
    temp.WriteAtCurrentPos(kTestAudioData, kTestAudioDataSize);

    // Corrupt the header.
    temp.Write(3, "0x00", 1);

    ASSERT_EQ(kTestAudioDataSize, static_cast<size_t>(temp.GetLength()));
    temp.Close();

    // Create AudioParameters which match those in the WAV data.
    AudioParameters params(AudioParameters::AUDIO_PCM_LINEAR,
        CHANNEL_LAYOUT_STEREO, 48000, 16, kNumFrames);
    std::unique_ptr<AudioBus> audio_bus = AudioBus::Create(2, kNumFrames);
    audio_bus->Zero();

    // Create a FileSource that reads this file.
    bool loop = false;
    FileSource source(params, temp_path, loop);
    EXPECT_EQ(0, source.OnMoreData(base::TimeDelta(), base::TimeTicks::Now(), 0, audio_bus.get()));

    // Confirm all frames are zero-padded.
    for (int channel = 0; channel < audio_bus->channels(); ++channel) {
        for (int frame = 0; frame < audio_bus->frames(); ++frame) {
            EXPECT_FLOAT_EQ(0.0, audio_bus->channel(channel)[frame]);
        }
    }
}

} // namespace media
